Degenerate $C$-distribution cosine functions and degenerate $C$-ultradistribution cosine functions in locally convex spaces

Marko Kosti\' c, Stevan Pilipovi\' c, Daniel Velinov

The main purpose of this paper is to investigate degenerate $C$-(ultra)distribution cosine functions in the setting of barreled sequentially complete locally convex spaces. In our…